Figure 3 : Electrophysiology of Schaffer collateral synapses in CA1 region of murine hippocampus with ablation of SPL.

From: Sphingosine 1-phosphate lyase ablation disrupts presynaptic architecture and function via an ubiquitin- proteasome mediated mechanism

Figure 3

(a) mEPSC frequency is significantly reduced and (b) mEPSC amplitude significantly increased in SPLfl/fl/Nesslices compared to controls. Cumulative frequencies of occurrence of mEPSC frequencies and mEPSC amplitudes are plotted. (b) Inset shows examples of mEPSC traces (black: control; red: SPLfl/fl/Nes), lower traces are normalized in amplitude. (c) normal basal synaptic transmission as shown in the input-output curves. (d) PPF is significantly reduced at Schaffer collateral synapses from SPLfl/fl/Nes mice compared to controls. Ratios of the initial slopes of fEPSP pairs are plotted. Inset shows example traces at 40 ms stimulus interval (black: control; red: SPLfl/fl/Nes). (e) LTP recorded in the hippocampal CA1 region after high frequency stimulation (100 Hz, 1 s) of Schaffer collaterals in control and SPLfl/fl/Nes slices is unchanged. fEPSP slopes are expressed as percentage of change from baseline recordings (taken to be 100%) and plotted against time. (f) blocking rate of the NMDA responses by 40 μM MK-801 does not significantly vary between control and SPLfl/fl/Nes synapses. Results are displayed as 3 point bins. (g) blocking rate of the NMDA responses elicited by short trains (3 pulses, 10 ms interval, 0.05 Hz) is slower at SPLfl/fl/Nes synapses compared to controls. Results are displayed as 3 point bins. (a,b) n: mEPSCs/mice, control: 4038/6, SPLfl/fl/Nes: 3886/6; data in c-g represent means ± SEM; c, n: slices/mice, control: 12/3, SPLfl/fl/Nes: 11/3; (d) n: slices/mice, control: 30/10, SPLfl/fl/Nes: 48/16; e, n: slices/mice, control: 15/5, SPLfl/fl/Nes: 19/6; (f) n: neurons/mice, control: 5/4, SPLfl/fl/Nes: 5/4; (g) n: neurons/mice, control: 6/4, SPLfl/fl/Nes: 6/5; unpaired t-test, ***P < 0.0001.